The present invention relates to a clinical thermometer used in thermometry for a tympanic membrane and, more particularly, to a clinical thermometer utilizing thermal radiation.
Popular conventional clinical thermometers are for contact type such as axillary or oral thermometry. These clinical thermometers do not necessarily reflect core temperatures of the living body. Thermometry accompanies time restrictions and limitations in terms of thermometric condition, i.e., a rest state, resulting in cumbersome operations.
Since 1960s, tympanic thermometry has received a great deal of attention because it reflects the temperature of the hypothalamus controlling a biological control function. However, methods in those days where dangerous; that is, they could cause the perforation of a tympanic membrane because a thermocouple or thermistor is directly brought into contact with the tympanic membrane. In addition, thermometry accompanies discomfort and pains. Therefore, tympanic thermometry has not been able to go beyond the range of physiological studies.
In recent years, attempts for detecting an infrared ray radiated from a tympanic membrane to measure a tympanic temperature within a short period of time in a noncontact manner have been made. For example, as disclosed in Japanese Patent Laid-Open No. 61-117422, a noncontact type tympanic thermometer called "First Temp" (tradename) is commercially available from Intelligent Medical Systems, U.S.A. General tympanic thermometry is put into practice.